Separation of metallic sulfid ores.



F. J. LYSTER. SEPARATION OF METALLIC SULFID ORES.

APPLICATION FILED MAY 8, 1913.

1,203,372 Patented Oct-31, 1916.

2 SHEETSSHEET 1.

TTQ

F. J. LYSTER.

SEPARATION OF METALLIC SULFID ORES.

APPLICATION FILED MAY 8. 1913.

1 206,372. Patented 001. 31,1916.

2 SHEETS-SHEET 2.

28911141153120 I S'VVUM HZOZ 3513A attozuma 4 UNITED sTATEs PAT NT OFFICE.

FLEURY JAMES LYSTER, 0 BRoKE IIILL, EW SOUTH- A ES, AUsTRALIA, ASSIGNOR, BY MEsNE ASSIGNMENTS, TO MINERALS SEPARATION AMERICAN SYNDICATE (1913-) LIMITED, OF LONDON, ENGLAND.

SEPARATION OF METALLIC SULFID ORES.

To all whom it may concern Be it known that I, FLEURY: JAMES LYsTER, subject of the King of Great Britain and Ireland, residing at Broken Hill, in the State of New South Wales,

Commonwealth of Australia, mill foreman, have invented certain new and useful Improvements in or Relating to the Separation of Metallic Sulfid Ores, of which the following is a specification.

This invention relates to certain improvementsin'the separation of minerals and particularly of mixed zinc and'lead sulfid ores. The object of this invention is to separate metalliferous portions of an ore, such for eXample,-as the sulfid of lead (galena) from other portions of the ore, as by a method of difierential or selective flotationseparation of lead sulfid' (galena) and zinc sulfid (blende) obtaining products relatively rich in lead on the one hand, and a zinc product relatively low in lead'on the other hand.

The flotation separation process employed is preferably the agitation-froth process of the general type described in United States Patents No. 835,120 to. Sulman, Picard and- Ballot, of November 6, 1906, No. 955,012 to H. L. Sulman, of April 12, 1910, No,

962,678 to Sulman, Greenway and Higgins, of June 28 1910, No. 1,064,723 to Gri'eenway and Lavers, of June 17,. 1913, and British Patent No. 18,943 of 1910 to Minerals Separation, Limited, as a communication from H. H. Greenway.

Further this invention is a developmentof that described in the previous United States Patent No. 1,067,485 to Nutter and Lavers, of July 15, 1913, that is to say, a separation is efiected between the different metallic sulfids inthe agitation-froth process by varying the controlling conditions and particularly the chemical constitution of the solution employed.

I have discovered that sulfid of lead (galena) may be separated from sulfid of zinc '(blende) without any prel1m1nary treatment by subjecting the ore or metal liferous materials to a flotation separatlon treatment at a low temperature with eucalyptus oil or other frothing agent and with agitation or aeration in a neutral or alkaline, but not an acid, solution of the sulfates, chlorids or nitrates of calcium, mag-- nesium, sodium, potassium or mixtures of Specification of Letters Patent.

I these substances.

associated from each other).

Patented Oct. 31 1916.

Application filed May 8, 1913. Serial No. 766,346.

I I have also discovered that neutral or alkaline, but not acid, solutions of other suitable substances can be employed such as sulfate of manganese, zinc, or iron, chlorid of barium, carbonate and bicarbonate of sodium or I tures of these substances. The suitability of any given substance-in a neutral or alkaline solution can be easily determlned by a laboratory. test as hereinafter described. i

I have found that mineralized Water such as 1s obtained from the underground worklng at Broken Hill, Australia. is a suitable potassium or mixsolution for carrying out my process. Such A water gives approximately the following analysis Gas. per gall. Total soluble solids 666 and is alkaline inreaction when-submitted to the usual test with methyl orange.

In carrying this process into effect a plant, I similar to that employed in and common to l flotation frothing processes is-employed, but the plant I recommendis illustrated in the accompanying drawings in which Figure 1 is a longitudinal elevationand F 1g. 2 a cross section of a unit with the supply devices in elevation. Fig. 3 is a sectional elevation of an apparatus suitable for' testing. I I will now describe my process as carried out in the apparatus shown in Figs. 1 and 2. -Tl1e ore is first ground to a suitable degree of fineness (preferably to slimes so that the different metallic sulfid particles are dis- This finely ground ore with its accompanying circuit water (which is a solution such as hereinbefore' described) is led, into asettler or thickener A to remove excess water.

The thickened pulp is then led into a vessel B frpm which it .passes to the first centrifugal pump C of series C C C C C C.

These centrifugal pumps are each connected to the individual members of a corresponding series of separating boxe s D,D D? ,.D*,

D D These centrifugal pumps act as agitators or mixers and means are provided (such as an inlet pipe E) for feeding in the requisite amount of eucalyptus oil or other frothing agent, about 2 lbs. per ton of material treated, as well as the requisite amount of air (such as by a tap F) into the suction pipe G thereof which is connected to the feed vessel 13. The centrifugal pump G draws in pulp, air, and frothing agent and produces an intimate mixture which is discharged through the outlet pipe H to the separatorfbox D, the delivery of the pump being controlled by the admission of air by the tap F. The particles of lead sulfid (galena) are found to rise to the top of the separator box D where an inverted pyramid J diverts the froth toward the discharge lip or launder K from which it flows to the receptacle for settling and collecting the lead concentrate. The particles which do not rise or float, together with the balance of the water, sink to the bottom of the .box D and are there withdrawn by the outlet pipe L which is connected to the suction pipe G of the next pump C of the series and the operation is repeated, the residues of one separator box D passing to the centrifugal pump C of the next in series. In the plant illustrated in the accompanying drawings there are six separator boxes and their attendant pumps which comprise one series or unit, but it will be understood that this number is dependent upon the proportion of mineral contained in the ore and the degree of agitation and aeration required, the repetition of the operations being carried on until the grade of the concentrates becomes too low in lead and the zinc begins to appear therein. The temperature I prefer is below 100 F. that is to say the operation is conducted at the ordinary temperature and no extraneous heat is utilized.

I have observed in working the process that an excessive alkalinity tends to retard the selective flotation of the lead sulfid particles. Therefore if the solution be alkaline the same should be only slightly alkaline but sufiicient to respond to the well known methyl orange test when the process is employed for the sulfid.

The suitability of the substances hereinbefore indicated and the proportion thereof to the solution and the degree and duration of agitation or aeration of the material *t'reated can be determined in a laboratory selective separation of lead or pipe S at'the bottom. In carrying out a test the mixing vessel N contains the solution which corresponds with the circuit water of the working plant, and eucalyptus oil or other frothing agent is then'added in measured quantities. The impeller O is then rotated at about 1700 revolutions per minute and a charge of about 448 grams of ore is fed in. Sufiicient solution is added to fill the. separating box P to the level of its discharge lip. The agitated pulp is forced through the passage R into the separating box P and the float or froth rising to the surface is skimmed off over the lip. The pulp is continuously circulated by being drawn from the bottom of the box P by the pipe S back into the mixer N by the action of the impeller O. The flotation is continued until the float or froth is noticed by observation to become lower in lead and the zinc begins to appear therein. The appearance of the concentrate being skimmed off over to the lip of the separating box will indicate the duration of agitation necessary to obtain a good concentrate combined with a good recovery while experience will indicate the amount of frothing agent necessary and further quantities may be added at intervals as found necessary. The residue is run ofi' from the bottom of the machine by disconnecting the flexible hose or pipe S. Repeateditrials with different solutions and with different strengths will indicate what is bestsuited to the particular ore under treatment. The ascertained duration of agitation and aeration will govern the number of separator boxes which will be necessary in the working plant when used.

The following examples are given of solutions which have been used by me in obtaining a selective separation of the lead sulfids that hereinbefore described is from the Zinc sulfids in what are known, as

ton.

Calcium sulfate grains per gallon.

Calcium sulfate 160 with Calcium hydrate 1. S Calcium sulfate 160 with Calcium hydrate 3. 6

Calcium chlorid 300 Calcium chlorid 300 with Calcium hydrate 1. 8 Calcium chlorid 300 with Calcium hydrate -3. 6 Calcium nitrate 300 Calcium nitrate 300 with Calcium hydrate 1. 8 Calcium nitrate 300 with Calcium hydrate 3.6 Calcium'nitrate 300 with Calcium hydrate 18 Magnesium s lfate 400 grains per gallon Magnesium sulfate 400 with Calcium hydrate i 1 8 Magnesium sulfate 400 with Calcium hydrate 3 6 u u Magnesium sulfate 400 I with Calcium hydrate 1 u u A Magnesium chlorid 300 {Magnesium chlorid 300 with Calcium hydrate 1 87 u l {Magnesium chlorid 300 w Calcium hydrate 3 6 H u Magnesium nitrate- E300 l, Magnesium nitrate 300 u I u with Calcium hydrat 8 u u l. Magnesium nitrate 300' u u u with Calcium hydrate 3 u u ll ,Magnesium nitrate 300 l l, u

with Calcium hydrate 18 u i u Sodium chlorid 800 u u n Sodium chlorid 800 u with Calcium hydrate 1, u Sodium chlorid 800 H u j with Calcium hydrate 6 u Sodium chlorid 800 H u with Calcium hydrate 18 u Potassium sulfate 300 H -l Potassium sulfate 300 with Calcium hydrate 1, 8

Potassium chlorid 800 Potassium chlorid 800 with Calcium hydrate 1, s H u Potassium chlorid 800 with 1 Calcium hydrate 3, 6 Potassium chlorld 800 with Calcium hydrate 18 Potassium nitrate e H Potassium nitrate with Calcium hydrate 8 Potassium nitrate with Calcium hydrate 15 Barium chlorld 300 M Barium chlorid 300 with Calcium hydrate 1.8 f Barium chlorld 300 with Calcium hydrate 3. 6

Sodium sulfate 800 f Sodium sulfate 800 H with Calcium hydrate 1. 8 Sodium sulfate 800 with f 4 Calcium hydrate 3. 6 Sodium sulfate 8 00 with (L Calcium hydrate 18 Sodium bicarbonate 6W Sodium carbonate 5 0 f Manganese sulfate 300 Zinc sulfate 500 f Ferrous sulfate 300 Alum 300 u I have further discovered that the residues obtained as before described containing the bulk of the zinc sulfids may be further treated by flotation separation to produce a concentrate rich in zinc by first dewatering and thickening the pulp and then submitting it to a repetition of the flotation separation, using however fresh water in lieu of the solution previously employed, or by furthercontinuing the 'process hereinbefore described, after the recovery of the lead sulfids (galena) in a separate de-zincing unit until the zinc sulfids (blende) appear upon the surface of the solution and are carried over into the launders hereinbefore mentioned. In' operation "I prefer the former to the latter method forthe recovery of the zinc sulfids (blends). In this way a zinc concentrate may be obtained and thereby bothlthe lead sulfids and zincsulfids recovered in separate products by flotation' separation without recourse to separation by gravitation, tables or vanners as heretofore.

Where the term abnormal amount is employed in the following claims-with reference to the salts in solution it is intended to mean that the amount of salts present is in excess. of that ordinarily found in natural fresh water.

I claim:

1.. A process for the separation of lead sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, which consists in subjecting the said ores to a flotation separation treatment by agitating them with a frothing agent in a non-acid solution of the mineral acid salts of metals which form' basic hydroxids and thereby separating the lead sulfid from the zinc sulfid.

2. A'process for the separation of lead sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, which consists. in subjecting the said ores to a flotation separation treatment by agitating them with a frothing agent inn slightly alkaline solution of the mineral acid salts of metals which form basic hydroxids, and thereby separating the. lead sulfid from the zinc sulfid.

3. A process for the separation of minerals which consists in subjecting a pulp of an ore containing mixed minerals to agitation and aerationj with a small proportion of a frothing agent in a non-acid solution containing in abnormal amount a plurality a of the mineral acid saltsfof metals which form basic hydroxids so asfby such agitat10n and aeration, to produce a froth of concentrates, said solution being non-acid during separation of the minerals, and separating the froth.

4. A process for the separation of minerals which consists in subjecting apulp of an ore containing mixed minerals to agitation and aeration with a small proportion v 5, A process for the separation of Iowa sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, which consists in subjecting the said ores to a flotation separation treatment by agitating them with eucalyptus oil in a non-acid solution of the mineral acid salts of metals which form basic hydroxids, and'thereby separating the lead sulfid from the zinc sulfid,

6. A process for the separation of lead sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, which consists in subjecting the said ores to a flotation separation treatment by agitating them with eucalyptus oil in a slightly alkaline solution of the mineral acid salts of metals which form basic hydroxide, and thereby separating the lead sulfid from the zinc sulfid.

7. A process for the separation of minerals which consists'in subjecting a pulp of an ore containing mixed minerals to agitation and aerationiwith a small'proportion of a frothing agent in a non-acid solution containing in abnormal amount the sulfates and chlorids of calcium, magnesium and manganese, so as, by such agitation and aeration, to produce a froth of concentrates, and separating the froth.

8. A process for the separation of minerals which consists in subjecting the pulp of an ore containing mixed minerals to agitation and aeration with a small proportion of a frothing agent in a slightly alkaline solution containing in abnormal amount the sulfates and chlorids of calcium, magnesium and manganese, so as, by such agitation and aeration, to produce a froth of concentrates,- and separating the froth.

9. A process for the separation of lead sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, which consists in subjecting the said ores to a flotation separation treatment at about atmospheric temperature by agitating them with a frothing agent in a non-acid solution of the mineral acid salts of metals which form basic hydroxide, thereby separating the lead sulfid from \the zinc sulfid and obtaining a concentrate relatively rich in lead. j

10. A process for the separation of lead sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, which consists in subjecting the said ores to a flotation separation treatment by agitating them with a frothing agent in a non-acid solution containing the sulfates and chlorids of calcium, magnesium and manganese, thereby separating the lead sulfid from the zinc sulfid.

11. A process for the separation of lead sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, which consists in subjecting the said ores to a flotation separation treatment by agitating them with a frothing agent in a slightly alkaline solution containing the sulfates and chlorids of calcium, magnesium and manganese, thereby separating the lead sulfid from the zinc sulfid.

12. A process for the separation of lead sulfid fromzinc sulfid in ores containing mixed lead and zinc sulfids, which consists in subjecting the said ores to a flotation separation treatment by agitating them with eucalyptus oil in a non-acid solution containing the sulfates and chlorids of calcium, magnesium and manganese, thereby separating the lead sulfid from the zinc sulfid.

13. A process for the separation of lead sulfid from zinc sulfid in ores containing mixed lead and zinc sulfids, whichconsists in subjecting the said ores to a flotation separation treatment by agitating them with eucalyptus oil in a slightly alkaline solution containing the sulfates and chlorids of calcium, magnesium and manganese, thereby separating the lead sulfid from the zinc sulfid. v r

In testimony whereof I have affixed my signature in presence of two witnesses.

FLEURY JAMES LYSTER.

Witnesses:

EDWARD J oHN TURNER, CHARLES STANLEY BURGESS. 

